Digital elevation models are utilized for many tasks such as tsunami modeling, modeling water flow for hydrology, flight simulation, navigation, and archaeology. Elevation models are usually based on series or sets of elevation measurements taken at physical locations. However, many sets of elevation measurements are created by different organizations using different measuring devices, with different reference levels and are stored in different formats. Different sets of elevation measurements often have different levels of coverage as well. For instance, one set of measurements may contain a few elevation measurements spread over a large physical area, while another set of measurements may contain several measurements clustered in a small physical area.